The capacity crowd had good reason to doubt that last night would ever come: in the three years since Fall Out Boy went on hiatus following their 2008 album Folie à Deux, each member of the pop-punk outfit continued to release new music – Stump put out the solo albu Soul Punk, Wentz went with his reggae-infused outfit Black Cards and Trohman and Hurley formed the Damned Things – but all made it a point to shoot down any rumors that their most band was, or would ever be, back in the saddle. (Wentz, usually the most loose-lipped of the bunch, kept his poker face until the bitter end: when theChicago Tribune sked him last weekend whether a Fall Out Boy reunion was happening, he replied "It's not.")

That changed on Monday morning when Fall Out Boy issued an unexpected press release announcing a new studio album Save Rock N' Roll, that's due May 7th, a tour and a last-minute string of intimate shows starting last night in Chicago. The band als released a new single, "My Songs Know What You Did in the Dark (Light Em Up)," to which nearly every fan seemed to know the words when the band played it live for the first time.

The crowd was on the brink of hysteria when Fall Out Boy took the stage just after 9 p.m., galloping triumphantly down a winding stairwell as "Thriller" blared overheard. "Hey Chicago, you guys all look pretty damn good right now!" shouted Stump, wearing a black leather jacket and matching hat and glasses so that he could see "how beautiful everyone was."

With little fanfare, the band quickly launched into the pummeling rock riot of "I Slept With Someone in Fall Out Boy and All I Got Was This Stupid Song Written About Me." The band didn't leave the audience much time to catch their breath, peeling off hits in quick succession, including quot;A Little Less Sixteen Candles, a Little More 'Touch Me,'" "Dead on Arrival" and "This Ain't a Scene, It's an Arm's Race."

The middle of the set seemed intended to please the diehards, many of whom had waited for hours in the blistering cold for a chance to see their heroes in such close proximity. Stump announced the band would be going "rapid-fire" with older, more rare material, then led the charge into a medley of lesser-played tunes that included two of the band's earliest numbers, "Honorable Mention" and "Calm Before The Storm."

All night the foursome acted as if no time had passed since they last played live together in 2009, and their onstage rapport was laid back. "This is an experience. This is an adventure. This isn't for your fuckin' Facebook," Wentz deadpanned at one point in the evening. Added Stump with a smirk, "Today is kind of a big deal for us.”

There were occasional cobwebs from the band's three-year break: Hurley and Trohman briefly fell out of sync during "I'm Like a Lawyer With the Way I'm Always Trying to Get You Off (Me & You)," and Stump admitted to the crowd that he was struggling to remember all the lyrics to the band's extensive catalog.

Those glitches aside, the band seemed as thrilled as the audience that Monday night was the start of Fall Out Boy's next chapter Wentz couldn't hide his excitement: late in the set, before leading his band into a cover of Michael Jackson's quot;Beat It," followed by their biggest hit "Sugar, We're Goin Down" and a killer encore that included "Thnks Fr Th Mmrs" and "Saturday," the bassist gazed out at the crowd and said, "You guys feel so fucking awesome!"

Set list

"Thriller""I Slept With Someone in Fall Out Boy and All I Got Was This Stupid Song Written About Me""A Little Less Sixteen Candles, a Little More 'Touch Me'""Dead on Arrival""This Ain’t a Scene, It’s an Arms Race""Nobody Puts Baby in the Corner""I'm Like a Lawyer With the Way I'm Always Trying to Get You Off (Me & You)""Tell That Mick He Just Made My List of Things to Do Today""Grand Theft Autumn/Where Is Your Boy""Hum Hallelujah""Dance, Dance""Honorable Mention""America’s Suitehearts""Calm Before the Storm""What a Catch, Donnie""The Take Over, the Breaks Over""I Don't Care""My Songs Know What You Did in the Dark Light (Light Em Up)”"Sophomore Slump or Combeack of the Year""Beat It""Sugar, We're Goin Down"